Abstract—The aim of this work is to assess the biomechanical
response or load transfer response between osteoporotic (with
first lumbar (L1) vertebral compression fracture) and healthy
vertebrae in five vertebral physiological motions namely as
compression, flexion, extension, lateral bending and axial
rotation. For this purpose, an image-basedheterogeneous
three-dimensional patient-specific of lumbar and thoracic
spinal unit (T12-L2) finite element models for healthy and
osteoporotic subjects were created.
The finite element analysis have shown that one of the most
significant effects of osteoporosis is the tendency to produce
higher stress and strain in the cancellous region of the vertebral
body. The maximum stress and strain was 4.53 fold
(compression) and 5.43 fold (axial rotation) higher for the
osteoporotic than the healthy subject, respectively, under the
similar loading activity. Uneven stress distribution patterns also
have been detected in the osteoporotic vertebrae rather than the
healthy vertebrae. All of these characteristicsare reflected bya
reduced structural strength and bone mass which might lead to
an increased risk of fracture. These results strengthen the
paradigm of a strong relationship between osteoporosis and its
high susceptibility to fracture.

M. H. Mazlan is with Kyushu University, Japan (e-mail:
hazli.010@s.kyushu-u.ac.jp).
M. Todo is with the Research Institute for Applied Mechanics, Kyushu
University, Japan (e-mail: todo@riam.kyushu-u.ac.jp).
Hiromitsu Takano and Ikuho Yonezawa are with the Department of
Orthopedic Surgery, Juntendo University School of Medicine, Japan (e-mail:
hrtakano@juntendo.ac.jp).